The effect of dietary supplement with 17% high-amylose barley (Hordeum vulgare, HAB) 'Karmose' on boar taint was studied on 72 crossbred entire male pigs (Sus scrofa domestica) Swedish Yorkshire dams x Swedish Landrace sires). All pigs were fed the same commercial diet (12.4 MJ metabolised energy (ME) per kg, digestible crude protein (CP) 13.5%) twice a day until the average live weight (LW) in the pen reached 100 +- 11.8 kg. Then, 32 out of 72 pigs received an HAB diet. Half of these pigs received HAB for 14 days and the other half for 28 days. The pigs were slaughtered at an average LW of 122.3 +- 8.6 kg (age 167.2 +- 7.5 days). The HAB diet did not affect performance, carcass and meat quality characteristics, and puberty status, but reduced plasma skatole levels in the pigs (least squares means, 3.6 vs. 2.0 ng mlE-1, P = 0.037). However, this diet failed to reduce skatole, indole and androstenone levels in fat (P is greater than 0.10). Nevertheless, it is desirable to continue investigation of HAB to optimise the feeding procedure to improve efficiency of HAB effect on fat skatole levels. Additionally, validation of a greater amount of HAB in the diet should be performed.

The production of innovative composition (high omega group fatty acids and antioxidants-carotenoids) broiler chicken meat and egg opportunities in Latvia was assessed. After feeding the poultry with feed enriched with fatty acids and antioxidants, broiler meat and eggs of innovative composition containing a higher amount of omega-3 (in meat by 1.7%, in eggs by 2.7%), omega-6 (in meat by 3.9%, in eggs by 3.2%) and carotenoids (0.44 mg kg-1 in meat and in eggs by 6.9 mg kg-1) when compared with the content of commercial products are obtained. Nutrition costs of innovative composition-based broiler chicken meat production are LVL 20 higher and nutrition costs of egg production are LVL 1.49 higher per 1000 units of output than in the standard version of the poultry feeding-stuff. The poultry farming production of an innovative composition, however, is economically profitable due to the higher rates of poultry productivity. In the case of an innovative composition-based yield the potential profit at the currently equal cost realisation of poultry meat and eggs is higher when calculating 293.47 LVL per 1000 broiler chickens and 5.52 LVL per 1000 eggs in comparison with commercial production.

Estimating feed intakes of individual cows in a loose-housed system is difficult and unreliable. It is known that estimating intakes from the number of bites taken at grazing is unreliable. Feeding from a total mixed ration (TMR) is likely to have fewer confounding variables. All cows were over 30 months old, of three breeds: Holstein Friesian, Estonian Red and Estonian Native. There were 30 feeding bins and 66 cows. Cows were observed over the whole 24 hour period, from 1st July to October 22nd 2011, in Märja experimental farm, of the Estonian University of Life Sciences, and data from 37 cows were collected. Measures taken included: time spent at the feed bin, number of bites taken at each visit, weight lost from the bin, and evidence of stealing. Mean time spent at each visit to the feed bin with standard error was 4.4 + 0.68 minutes. The mean number of bites per visit was 7.1 + 1.01. There was a significant correlation between the number of bites and total time cows spent feeding (p is less than 0.001), with a regression R2 value of 79.8%. No correlation was found between the number of bites and feed removed at each visit (p=0.851) nor between the time per visit and amount of feed removed (p=0.681). Therefore, there is no evidence that either the number of bites taken per visit or the time spent at bin per visit is related to intakes. There was no effect of age. Stealing was evident and widespread.

Studies have been conducted to find out the effect of the feeding of calves (Bos Taurus) with Jerusalem artichoke (Helianthus tuberosus) concentrate produced in Latvia containing the prebiotic – inulin. The study was performed on two groups of animals - a control group of 8 animals and test (prebiotic) group of 8 animals in summer (from June to August, 2013), and winter (from December, 2013 to February, 2014) in one of cow farm of Latvia, in the municipality of Bauska. Both groups were fed the whole milk, but the test group received additionally 12 g of Jerusalem artichoke powder (an average of 500 g kgE-1 inulin) per day. The overall health status and physiological parameters (temperature, heartbeat and breathing frequency) of both animal groups before the study were of the normal range. After the experiment, we found out that the calves of the test group during both winter (one case) and summer seasons (seven cases), had fewer cases of diarrhea than the control (winter months four cases and summer months nine cases) group animals, the average daily weight gain (control group 0.53 g, prebiotic group 0.75 g) and the total weight gain (control group 29.42 kg, prebiotic group 42.13 kg) during 56 test days was significantly higher ( p is less than 0.05) than that for the control animals. We concluded that the use of Jerusalem artichoke flour concentrate when fed to the calves generally gives positive impact on the development and growth of the calves, improves the status of the gastrointestinal tract and the morphometric indicators.

In goats (Capra) the growth and functional development of certain parts of the multi-chambered stomach continue during the first few months after birth. The aim of this research was to clarify morphofunctional changes in the kids abomasa and rumina and live weight gain during the first 8 weeks of life. Research was performed in two parts. In the first part (P1) we used Saanen breed kids which were all kept in the same conditions and in the second part (P2) we used Saanen breed kids which were separated in two groups with different feeding diets. In P1 the stomach contents of the goat kids were collected after slaughter (on day 1, 17, 25 and 30), weighed full and empty. The gastrohromoscopical method proved that in the newborn kids the area where the abomasal pH is 3.0 and lower is about 10% of the surface of the abomasum, but in age of three weeks it is composing 80% of the mucosal surface of the abomasum. In P2 were two groups – in the first group (MMG) kids which were fed with dairy (mother) milk and lived with mothers, the second group (MRG) kids were fed with milk replacer and lived separate from mothers. The stomach contents were collected after slaughter(at day 45 and 60).We confirm that the most important age of stomach development and kids growth in postnatal period are the first 45 days. During this period the most significant differences can be observed. On day 60 there are no significant differences (p is greater than 0.05) between MMG and MRG stomach development.

Nutritional value and shelf life of milk and dairy products depend on the composition and stability of their constituents. The aim of the present study was to evaluate the effects of carrots as cow feed carotenoid source on butter oil fatty acid (FA) composition and oxidative stability. Milk was obtained from one trial group (TG; n=5) and one control cow group (CG; n=5) in a conventional dairy farm in Latvia. TG cows received carrots 7 kg per cow per day; the length of the supplementation period was 39 days. The stability of butter oil exposed to sunlight (3h) and held for 14 days in the temperature of 60 °C was analyzed by peroxide value method. The changes of the FA content and ratios in TG milk fat were more positive with respect to the fat nutritional value as observed in CG – stronger increase in the content of polyunsaturated FA (p is less than 0.05), and in the ratio between stearic and palmitic acids (p is less than 0.05); also a tendency was seen of increasing content of short and monounsaturated FA, as well as decreasing the ratio between ω6 and ω3 FA groups. Oxidative stability of the carrot supplemented cow group’s milk butter oil samples that were collected after 25- day trial period, exposed to sunlight (3h) and stored at a temperature of 60 °C was significantly (p is less than 0.05) higher compared to CG samples. After the 39-day long trial period stability difference was not significant, despite the tendency that average polyunsaturated FA content in TG samples was higher compared to the control.

The quality and nutritional value of milk and dairy products are considerably influenced by the stability of its constituents. The aim of the present study was to evaluate the possibility of enhancing oxidative stability of cow’s milk fat and vitamin B2 using carrots and palm oil feed supplement CAF 100 as sources of natural antioxidants in cow feed. Milk samples were collected after 25-day period of feed supplementation. The intensity of riboflavin losses during its photo oxidative degradation in sunlight was measured by the fluorometric method. A slight and significant (p is less than 0.05) difference in higher vitamin B2 stability was seen in carrot-supplemented group (TG1) milk, where the losses of vitamin B2 were by 3.01% less compared to CG (CG). The oxidative stability of butter oil samples stored in 60 °C temperature was analyzed by peroxide value (PV) method. The oxidative stability of samples initially affected by light from both trial groups was significantly (p is less than 0.05) higher compared to CG showing the good potential of the cow diet enrichment with carotenoid additives. The longest induction period (larger than 14 days) was observed in CAF-100- supplemented (TG2) cow milk fats, which can be explained by carotenoids and tocopherol presence and its possible synergism in fat protection. The induction periods of the TG1 and CG were 12.03 and 10.97 days, respectively.

β-Carotene (BC) and a-tocopherol in milk fat have positive implications in human nutrition, besides the specifically protecting polyunsaturated fatty acids from oxidation. To determine the possible effect on some milk components, nutritional value and lipid stability of including carrots in the diet of lactating cows, ten cows were selected in a dairy farm and divided into 2 groups (control and experimental) by 5 cows in each. In experimental group's diet additionally 7 kg carrots per cow per day were included. Individual cow milk samples were obtained 1 day before feed enrichment, in days 7, 24, 35, 42 (during the feed enrichment), and 1 week after feed enrichment. Analyses of milk fat, protein content, somatic cell count (SCC), retinol, BC, vitamin C, tocopherols, immunoglobulins (Ig), lysozyme, fatty acids (FA) were made, and milk yield was measured. Supplying cow diet with carrots showed a tendency to improve milk quality by promoting the faster decrease of SCC, and significantly (p is less than 0.05) increasing Ig and lysozyme content, thus potentially improving milk nutritional value. The vitamin content rose significantly (p is less than 0.05) by retinol and tocopherol contents, but b-carotene content increase in milk was not observed. Also milk fatty acid (FA) stability changes during 5 day storage in temperature of 4 - 6 deg C were not observed.

Methane is considered to be the main greenhouse gas (GHG) emitted by livestock. One method for reducing methane emissions from ruminants is to improve production efficiency, which reduces methane emissions per unit of product (FAO, 2010; Gworgwor, Mbahi, and Yakubu, 2006). There are many researches about prebiotics which can reduce methane production in livestock, for example, galacto-oligosaccharides reduced methane emission up to 11% (litres/day) (Zhou et al., 2004). There is almost no information about prebiotic inulin, so the aim of this research was to determine the impact of different dosages of inulin concentrate (50%) on the increase of calves’ body weight and its impact on methane emission, as well as to find out how the results change if it is added to barley flour not to milk as in our previous research. Approximately fifty days old, clinically healthy, different Holstein Friesian crossbreed calves kept in groups of 8, in a partly closed space with natural ventilation through windows were included in this research. Eight calves were in the control group (CoG) and sixteen received inulin (Pre12 (n = 8), Pre24 (n = 8)). At the beginning of the experiment – the 28th and 56th day - we determined each calf’s weight and measured the methane level in the rumen by using the PICARROG-2508 gas analyser (Fleck, 2013). We concluded that inulin supplement significantly (p ≤ 0.05) increased the live weight gain comparing Pre24 and CoG. The highest methane production on 1 kg of body weight at the end of the research was detected in Pre24 – 1.24 mg mE-3 and the lowest in CoG – 0.99 mg mE-3.

Cattle fattening, first of all, should be beneficial for a farmer, therefore, in Latvia more suitable are such average intense fattening methods as fattening with grass fodder. In the world, demand for beef, produced in an environmentally friendly manner, ensuring the appropriate animal welfare conditions, is growing. The aim of the study was to find out the fattening results of Hereford (HE) and Aberdinanguss (AB) pure-bred bulls and their crosses when fed with grass fodder. The study was conducted in 2015 and 2016 within the framework of the project ‘Baltic Grassland Beef’. AB crossbreed bulls were slaughtered when they were 519 ± 16.6 days old, but HE pure-bred bulls − 584 ± 7.3 days old (p ≤ 0.05). The biggest live weight and slaughter weight showed HE crossbreed group bulls – 557 ± 19.4 kg and 293 ± 12.2 kg, respectively, but the biggest live weight daily gain from birth to slaughter was observed to AB pure–bred group bulls – 952 ± 24.7. Carcass conformation score in muscle development was the highest for AB pure–bred group bulls. Their average conformation score was 3.2 ± 0.08 points. In terms of fat score development, carcass with the best quality was obtained from HE crossbreed group bulls, the resulting fat score – 2.4 ± 0.10. The obtained results prove that pure-bred and crossbreed bulls used in this research are suitable for fattening with grass in the conditions of Latvia